Etomidate: applications in pediatric critical care and pediatric anesthesiology

Anesthetic considerations for extracranial injuries in patients with associated brain trauma

Patients with severe traumatic brain injury often presents with extracranial injuries, which may contribute to fatal outcome. Anesthetic management of such polytrauma patients is extremely challenging that includes prioritizing the organ system to be dealt first, reducing on-going injury, and preventing secondary injuries. Neuroprotective and neurorescue measures should be instituted simultaneously during extracranial surgeries. Selection of anesthetic drugs that minimally interferes with cerebral dynamics, maintenance of hemodynamics and cerebral perfusion pressure, optimal utilization of multimodal monitoring techniques, and aggressive rehabilitation approach are the key factors for improving overall patient outcome.

Etomidate Versus Ketamine: Effective Use in Emergency Procedural Sedation for Pediatric Orthopedic Injuries

OBJECTIVES

The aim of this study was to compare the induction and recovery times, postsedation observation durations, and adverse effects of etomidate and ketamine in pediatric patients with fractures and/or dislocations requiring closed reduction in the emergency department.

METHODS

Forty-four healthy children aged 7 to 18 years were included. The patients were randomly divided into 2 groups. Group 1 (24 patients) received etomidate and fentanyl, and group 2 (20 patients) received ketamine intravenously. The Ramsay Sedation Scale and American Pediatric Association discharge criteria were used to evaluate the patients.

RESULTS

There were 70 fractured bones and 3 joint dislocations. Except in 1 case (2.3%), all of the injuries were reducted successfully. The mean amount of drugs used to provide adequate sedation and analgesia were 0.25 mg/kg of etomidate and 1.30 μg/kg of fentanyl in group 1 and 1.25 mg/kg of ketamine in group 2. Fourteen patients (31.8%) reported adverse effects, and none required hospitalization. There was no difference between the groups in the recovery times, occurrence of adverse effects, and postsedation observation durations (P > 0.05). The mean (SD) induction time for the patients in group 1 was 4.3 (1.0) minutes, whereas it was 2.2 (1.6) minutes in group 2 (P < 0.001).

CONCLUSIONS

Etomidate induces effective and adequate sedation in the pediatric emergency department for painful orthopedic procedures. Ketamine, which has longer action times, might be preferred for reductions because orthopedic procedures could be lengthy.

Update on the 2012 guidelines for the management of pediatric traumatic brain injury - information for the anesthesiologist

Traumatic brain injury (TBI) is a significant contributor to death and disability in children. Considering the prevalence of pediatric TBI, it is important for the clinician to be aware of evidence-based recommendations for the care of these patients. The first edition of the Guidelines for the Acute Medical Management of Severe Traumatic Brain Injury in Infants, Children, and Adolescents was published in 2003. The Guidelines were updated in 2012, with significant changes in the recommendations for hyperosmolar therapy, temperature control, hyperventilation, corticosteroids, glucose therapy, and seizure prophylaxis. Many of these interventions have implications in the perioperative period, and it is the responsibility of the anesthesiologist to be familiar with these guidelines.

Pro-con debate: etomidate or ketamine for rapid sequence intubation in pediatric patients

When caring for critically ill children, airway management remains a primary determinant of the eventual outcome. Airway control with endotracheal intubation is frequently necessary. Rapid sequence intubation (RSI) is generally used in emergency airway management to protect the airway from passive regurgitation of gastric contents. Along with a rapid acting neuromuscular blocking agent, sedation is an essential element of RSI. A significant safety concern regarding sedatives is the risk of hypotension and cardiovascular collapse, especially in critically ill patients or those with pre-existing comorbid conditions. Ketamine and etomidate, both of which provide effective sedation with limited effects on hemodynamic function, have become increasingly popular as induction agents for RSI. However, experience and clinical investigations have raised safety concerns associated with both etomidate and ketamine. Using a pro-con debate style, the following manuscript discusses the use of ketamine versus etomidate in RSI.

Perioperative management of the pediatric patient with traumatic brain injury

TBI and its sequelae remain a major healthcare issue throughout the world. With an improved understanding of the pathophysiology of TBI, refinements of monitoring technology, and ongoing research to determine optimal care, the prognosis of TBI continues to improve. In 2003, the Society of Critical Care Medicine published guidelines for the acute management of severe TBI in infants, children, and adolescents. As pediatric anesthesiologists are frequently involved in the perioperative management of such patients including their stabilization in the emergency department, familiarity with these guidelines is necessary to limit preventable secondary damage related to physiologic disturbances. This manuscript reviews the current evidence-based medicine regarding the care of pediatric patients with TBI as it relates to the perioperative care of such patients. The issues reviewed include those related to initial stabilization, airway management, intra-operative mechanical ventilation, hemodynamic support, administration of blood and blood products, positioning, and choice of anesthetic technique. The literature is reviewed regarding fluid management, glucose control, hyperosmolar therapy, therapeutic hypothermia, and corticosteroids. Whenever possible, management recommendations are provided.

Cardiac arrest following ketamine administration for rapid sequence intubation

Given their relative hemodynamic stability, ketamine and etomidate are commonly chosen anesthetic agents for sedation during the endotracheal intubation of critically ill patients. As the use of etomidate has come into question particularly in patients with sepsis, due to its effect of adrenal suppression, there has been a shift in practice with more reliance on ketamine. However, as ketamine relies on a secondary sympathomimetic effect for its cardiovascular stability, cardiovascular and hemodynamic compromise may occur in patients who are catecholamine depleted. We present 2 critically ill patients who experienced cardiac arrest following the administration of ketamine for rapid sequence intubation (RSI). The literature regarding the use of etomidate and ketamine for RSI in critically ill patients is reviewed and options for sedation during endotracheal intubation in this population are discussed.

Efeitos da infusão contínua de propofol ou etomidato sobre variáveis intracranianas em cães

Avaliaram-se os efeitos da infusão contínua de propofol ou de etomidato sobre as variáveis intracranianas em cães nomocapneicos. Foram utilizados 20 cães adultos distribuídos aleatoriamente em dois grupos: grupo propofol (GP) e grupo etomidato (GE). Para o GP, os animais foram induzidos à anestesia com propofol (10mg/kg) e, ato contínuo, iniciaram-se a infusão do fármaco (0,6mg/kg/min) e a ventilação controlada. No GE, o etomidato foi usado para indução (5mg/kg) e manutenção empregando-se a dose de 0,5mg/kg/min nos 10 minutos iniciais e, em seguida, de 0,2mg/kg/min. Após 30 minutos da implantação do cateter de fibra óptica do monitor de pressão intracraniana (PIC) na superfície do córtex cerebral direito, realizaram-se as primeiras mensurações (M1) da PIC, da pressão de perfusão cerebral (PPC), da temperatura intracraniana (TIC), de temperatura corpórea (TC), da pressão arterial média (PAM) e da frequência cardíaca (FC). As demais mensurações ocorreram em intervalos de 20 minutos (M2, M3 e M4). O propofol e o etomidato não ocasionaram alterações significativas nas variáveis estudadas com exceção da TC e TIC. Concluiu-se que a infusão contínua desses fármacos em cães mantém a perfusão cerebral e a autorregulação cerebral. Cães anestesiados com etomidato apresentam efeitos adversos intensos e redução gradativa da temperatura corpórea e intracraniana.

Perioperative care of an adolescent with postural orthostatic tachycardia syndrome

Postural orthostatic tachycardia syndrome (POTS) is a disorder characterized by postural tachycardia in combination with orthostatic symptoms without associated hypotension. Symptoms include light-headedness, palpitations, fatigue, confusion, and anxiety, which are brought on by assuming the upright position and usually relieved by sitting or lying down. Given the associated autonomic dysfunction that occurs with POTS, various perioperative concerns must be considered when providing anesthetic care for such patients. We present an adolescent with POTS who required anesthetic care during posterior spinal fusion for the treatment of scoliosis. The potential perioperative implications of this syndrome are discussed.

Newer agents for rapid sequence intubation: etomidate and rocuronium

The emergency airway management of children and adolescents with critical illnesses may necessitate rapid sequence intubation with a sedating and a neuromuscular blocking agent. Etomidate and rocuronium have become increasingly popular for the sedation and paralysis, respectively, of pediatric patients in rapid sequence intubation, and there are many advantages to the use of both agents. Both etomidate and rocuronium have a rapid onset of action, and both agents are relatively free of hemodynamic adverse effects. Etomidate does, however, suppress adrenal function, and consequently, its use in patients with septic shock is controversial. Rocuronium can produce optimal intubating conditions without the serious complications that can accompany succinylcholine. The available evidence supports the safety of etomidate and rocuronium in rapid sequence intubation but also suggests that more prospective studies are needed in pediatric patients.

A survey of sedation assessment and management in Australian and New Zealand paediatric intensive care patients requiring prolonged mechanical ventilation

INTRODUCTION

A retrospective analysis of sedation management for children receiving prolonged ventilation in one Australian paediatric intensive care unit (PICU) revealed no identifiable pattern in sedation management and an inadequacy in the sedation scoring system. Therefore, the investigators sought to explore the current practice of sedation in critically ill children in PICUs across Australia and New Zealand.

METHOD

This study used a mail-out survey to audit sedation management within the eight dedicated Australian and New Zealand PICUs.

RESULTS

100% of the units surveyed replied (n=8). There were a total of 6,133 admissions to 8 Australian and New Zealand PICUs, where 3036 (49.5%) required ventilation. Of these children, 888 (29.2%) required ventilation > or =72 hours. Only 4 units had written guidelines for sedation management. A combined sedation regime of benzodiazepines and opioids was employed in six units. Administration and titration of sedation agents was managed by nursing staff alone in six units. All units indicated that they aimed to achieve a 'moderate level' of sedation. Two units used designated assessment tools for sedation and withdrawal assessment. One unit utilised Bispectral Index (BIS) monitoring.

CONCLUSION

There were similarities observed in the methods and types of sedation agents used within Australian and New Zealand PICUs. However, only half of the units had guidelines for sedation management, and most units did not use validated paediatric scales to assist staff in assessing patient sedation and pain levels. Therefore it is recommended that a standardised approach to sedation assessment and management of critically ill children requiring prolonged ventilation be developed and tested.

Use of etomidate as an induction agent for rapid sequence intubation in a pediatric emergency department

OBJECTIVES

Although etomidate is widely used for rapid sequence intubation (RSI), there is no consensus on the optimal induction agent and no prospective pediatric emergency department (ED) study exists. The objective of this study was to assess the effectiveness and safety of etomidate as an induction agent for RSI in the pediatric ED.

METHODS

Data on RSI conditions and complications were collected prospectively on patients undergoing RSI in a tertiary pediatric ED from January 2003 to December 2003. ED hemodynamic data and inpatient data were collected retrospectively via chart review.

RESULTS

Seventy-seven of 101 patients requiring intubation underwent RSI with etomidate. The mean (+/- SD) age was 8.2 (+/- 6.2) years. All 77 patients were successfully intubated. Intubation condition data were available for 69 of 77 patients (89.6%). Conditions were good in 68 of 69 (99%; 95% confidence interval = 92.2% to 99.9%). The mean (+/- SD) maximal percent decrease in systolic blood pressure was 10% (+/- 13.6%). A greater than 20% maximal percent decrease in systolic blood pressure occurred in 12 of 69 patients (17.4%; 95% confidence interval = 9.3% to 28.4%). There was no relationship between seizures after etomidate administration and prior seizure history (p = 0.25). Corticosteroids were given to 29 of 77 patients post-RSI for varying diagnoses. All eight patients given corticosteroids for shock were in shock at the time of intubation.

CONCLUSIONS

In the pediatric ED setting, etomidate as an induction agent provided successful RSI conditions and resulted in varied hemodynamic changes that were especially favorable in those patients presenting in decompensated shock. Hypotension and seizures were uncommon and occurred in patients with confounding diagnoses. Until the significance of a single dose of etomidate on adrenal dysfunction is further clarified, caution should be used in those patients at risk for adrenal insufficiency.

The effect of etomidate on intracranial pressure and systemic blood pressure in pediatric patients with severe traumatic brain injury

OBJECTIVE

To evaluate the effects of single-dose etomidate in pediatric patients with intracranial hypertension after severe traumatic brain injury.

METHODS

Patients admitted to the pediatric intensive care unit with severe traumatic brain injury were enrolled with the informed consent of their guardians. The experimental intervention was a single dose of etomidate 0.3 mg/kg intravenously. This dosage was administered only when enrolled patients had acute elevations of intracranial pressure (ICP) to over 20 mm Hg for over 5 minutes. ICP and mean arterial pressure (MAP) were monitored continuously. ICP and MAP values for 6 consecutive 5-minute intervals after etomidate administration were averaged for all patients and compared with baseline.

RESULTS

Eight patients were enrolled. Mean ICP after etomidate administration was significantly lower than baseline ICP for each 5-minute interval (P < 0.05). The mean MAP for all patients increased from baseline during the first 5-minute interval, but this change was not statistically significant. No patient's MAP decreased below baseline at any time point.

CONCLUSIONS

In pediatric patients with severe traumatic brain injury, single-dose etomidate administration resulted in statistically significant reductions in ICP and improvement in cerebral perfusion pressure without significantly altering MAP.

Anaesthesia for minimally invasive surgery in children

There continues to be an increase in the applications of minimally invasive surgical techniques in infants and children. This increase includes their use for new surgical procedures as well as their application in younger patients including neonates. As with any new surgical procedure, specific modifications of the anaesthetic technique may be necessary. This chapter reviews (1) the pre-operative evaluation of infants and children scheduled for minimally invasive surgery; (2) techniques for pre-medication and anaesthetic induction; (3) intra-operative anaesthetic implications of laparoscopy, including the cardiorespiratory consequences of CO2 pneumoperitoneum; (4) intra-operative anaesthetic implications of thoracoscopy, including techniques for one-lung ventilation (OLV); and (5) post-operative issues, including pain management and monitoring of cardiorespiratory function as they apply to the patient of paediatric age.